Apparatus for heating liquid, such as water, are well known in the art. Such apparatus typically include a tank for storing the heated liquid, a liquid fill line coupled to the tank for introducing the liquid to be heated into the tank and a heated liquid discharge line coupled to the tank for discharging heated liquid from the tank for external use, such as for domestic use and/or for space heating. One problem associated with such heating apparatus is that air and other gas are released from solution when the liquid is heated and may accumulate in the tank, particularly at the top thereof.
There is therefore a need for apparatus to prevent accumulation of air and other gases in a liquid storage tank.